syzbot


INFO: task hung in vfs_rename (3)

Status: auto-obsoleted due to no activity on 2026/06/12 21:27
Subsystems: jfs
Labels: prio:high
[Documentation on labels]
First crash: 94d, last: 94d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
9e0b9f8c-7d69-422d-8221-6fe42fb6c905 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: task hung in vfs_rename (3) 2026/05/25 07:57 2026/05/25 07:57 2026/05/25 08:53 c69befb30ac10e158cc9d1557b508ee3f0eca1de

			
		
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in vfs_rename 1 1 766d 766d 0/3 auto-obsoleted due to no activity on 2024/08/20 18:33
upstream INFO: task hung in vfs_rename fs 1 80 524d 639d 0/29 auto-obsoleted due to no activity on 2025/03/20 07:53
upstream INFO: task hung in vfs_rename (2) fs 1 C error error 15 302d 420d 0/29 auto-obsoleted due to no activity on 2025/12/04 18:25
linux-5.15 INFO: task hung in vfs_rename (2) 1 2 632d 633d 0/3 auto-obsoleted due to no activity on 2025/01/01 05:06

Sample crash report:
INFO: task syz.2.94:6515 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.94        state:D stack:22648 pid:6515  tgid:6514  ppid:5805   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6908
 __schedule_loop kernel/sched/core.c:6990 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 vfs_rename+0x68a/0xeb0 fs/namei.c:5989
 filename_renameat2+0x539/0x9c0 fs/namei.c:6144
 __do_sys_rename fs/namei.c:6188 [inline]
 __se_sys_rename+0x55/0x2c0 fs/namei.c:6184
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd36004c799
RSP: 002b:00007fd35e29e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007fd3602c5fa0 RCX: 00007fd36004c799
RDX: 0000000000000000 RSI: 0000200000000400 RDI: 00002000000003c0
RBP: 00007fd3600e2c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd3602c6038 R14: 00007fd3602c5fa0 R15: 00007ffc620e2fa8
 </TASK>
INFO: task syz.2.94:6539 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.[  314.701408][   T39] task:syz.2.94        state:D stack:27000 pid:6539  tgid:6514  ppid:5805   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6908
 __schedule_loop kernel/sched/core.c:6990 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7005
 io_schedule+0x80/0xe0 kernel/sched/core.c:7832
 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
 txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:375
 jfs_truncate_nolock+0x170/0x340 fs/jfs/inode.c:386
 jfs_truncate+0xce/0x140 fs/jfs/inode.c:420
 jfs_setattr+0x4f8/0x760 fs/jfs/file.c:123
 notify_change+0xc18/0xf60 fs/attr.c:556
 do_truncate+0x1c2/0x250 fs/open.c:68
 handle_truncate fs/namei.c:4279 [inline]
 do_open fs/namei.c:4675 [inline]
 path_openat+0x2fc4/0x38a0 fs/namei.c:4830
 do_file_open+0x23e/0x4a0 fs/namei.c:4859
 do_sys_openat2+0x113/0x200 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd36004c799
RSP: 002b:00007fd35e27d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd3602c6090 RCX: 00007fd36004c799
RDX: 0000000000103a42 RSI: 0000200000000440 RDI: ffffffffffffff9c
RBP: 00007fd3600e2c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000032 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd3602c6128 R14: 00007fd3602c6090 R15: 00007ffc620e2fa8
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/39:
 #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5553:
 #0: ffff8880368aa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by udevd/5843:
5 locks held by syz.2.94/6515:
 #0: ffff88803c104480 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
 #1: ffff88803c104880 (&type->s_vfs_rename_key#3){+.+.}-{4:4}, at: lock_rename fs/namei.c:3760 [inline]
 #1: ffff88803c104880 (&type->s_vfs_rename_key#3){+.+.}-{4:4}, at: __start_renaming+0xed/0x410 fs/namei.c:3852
 #2: ffff888060db8f78 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
 #2: ffff888060db8f78 (&type->i_mutex_dir_key#12/1){+.+.}-{4:4}, at: lock_two_directories+0x1a2/0x220 fs/namei.c:3736
 #3: ffff88805f9e5d78 (&type->i_mutex_dir_key#12/5){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
 #3: ffff88805f9e5d78 (&type->i_mutex_dir_key#12/5){+.+.}-{4:4}, at: lock_two_directories+0x1cc/0x220 fs/namei.c:3737
 #4: ffff888060db85b8 (&sb->s_type->i_mutex_key#30/4){+.+.}-{4:4}, at: vfs_rename+0x68a/0xeb0 fs/namei.c:5989
3 locks held by syz.2.94/6539:
 #0: ffff88803c104480 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
 #1: ffff888060db85b8 (&sb->s_type->i_mutex_key#30){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1033 [inline]
 #1: ffff888060db85b8 (&sb->s_type->i_mutex_key#30){+.+.}-{4:4}, at: do_truncate+0x18f/0x250 fs/open.c:63
 #2: ffff888060db8168 (&jfs_ip->rdwrlock#2){++++}-{4:4}, at: jfs_truncate+0xb2/0x140 fs/jfs/inode.c:419
3 locks held by syz.7.412/8566:
1 lock held by udevadm/8576:
2 locks held by syz.5.413/8581:
2 locks held by sed/8588:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xfd9/0x1030 kernel/hung_task.c:515
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5843 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:mas_validate_parent_slot lib/maple_tree.c:6988 [inline]
RIP: 0010:mt_validate+0x85d/0x4340 lib/maple_tree.c:7172
Code: 00 00 e8 76 cc a8 f6 48 c7 c7 60 e9 b8 99 be 04 00 00 00 e8 a5 df 0e f7 f0 ff 05 ae 4f 9d 0e eb 0e 4d 39 fc 0f 84 f6 00 00 00 <e8> 4e cc a8 f6 48 39 5c 24 18 0f 84 be 01 00 00 e8 3e cc a8 f6 49
RSP: 0018:ffffc900051cf5c0 EFLAGS: 00000287
RAX: ffffffff8b1b9954 RBX: 0000000000000000 RCX: ffff88805e113d00
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000
RBP: ffffc900051cf7b0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff3371d2c R12: ffff888032f73a0c
R13: ffff888032f73650 R14: 0000000000000003 R15: ffff88805d592e0c
FS:  00007f9a72da6880(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f507ebf5440 CR3: 000000005d5a4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 validate_mm+0xd4/0x4c0 mm/vma.c:649
 vms_complete_munmap_vmas+0x9b1/0xc60 mm/vma.c:1345
 do_vmi_align_munmap+0x3bd/0x4d0 mm/vma.c:1585
 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1633
 __vm_munmap+0x22c/0x3d0 mm/vma.c:3254
 __do_sys_munmap mm/mmap.c:1078 [inline]
 __se_sys_munmap mm/mmap.c:1075 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1075
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a72f0b097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc5a64f218 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 000055b8dd399fa0 RCX: 00007f9a72f0b097
RDX: 000055b8dd395420 RSI: 0000000000000200 RDI: 00007f9a7245a000
RBP: 000055b8dd395420 R08: 0000000000000030 R09: 00007ffc5a64f1f0
R10: 000055b8dd395410 R11: 0000000000000246 R12: 00007f9a735e81e0
R13: 00007f9a735ea39c R14: 0000000000000031 R15: 0000000000000001
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/14 21:21 upstream 69237f8c1f69 ee8d34d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in vfs_rename
* Struck through repros no longer work on HEAD.